There are nitride semiconductor wafers in which a semiconductor layer including nitride semiconductor is formed on a silicon substrate. Nitride semiconductor wafers are used in manufacturing e.g. light emitting diodes (LED), high speed electronic devices, or power devices. Nitride semiconductor wafers have the problem of being prone to cracks occurring in the semiconductor layer during manufacturing due to difference between the thermal expansion coefficient of the silicon substrate and the thermal expansion coefficient of the semiconductor layer. There is an approach for suppressing the occurrence of cracks by applying compressive stress to the nitride semiconductor layer. However, applying compressive stress to the nitride semiconductor layer makes it difficult to reduce threading dislocations.